Pathogenic role of oxidative and nitrosative stress in primary biliary cirrhosis

Figure 7 Immunohistochemical localization of aquaporin 8 in mouse hepatocytes. Considerable aquaporin 8 (AQP8) immunoreactivity (brown staining) is seen within the cytoplasmic compartment of most hepatocytes. Periodic acid-Schiff (PAS) reactivity (red staining) is seen over glycogen granules. In rodents, hepatocyte AQP8 is expressed at multiple subcellular levels, including the apical (canalicular) plasma membrane, subapical vesicles, smooth endoplasmic reticulum, and mitochondria. The AQP8 channel features conductance to water, ammonia, and H₂O₂, and is suggested to be involved in primary bile secretion, ammonia detoxification, ureagenesis, and mitochondrial reactive oxygen species generation. Original magnification, × 1000. (micrograph from Ferri et al[22], reproduced with permission from Wiley Online Library).